The present invention relates to a device for introducing and exchanging a casting or pouring tube with a mounted movable plate or flange for a sealable container for the iron and steel or metallurgy industries, equipped with a base plate of refractory material provided with a casting orifice, for another casting or pouring tube also having an attached plate or flange, for producing blooms and small slabs, notably in continuous casting or pouring distributors.
The majority of sealing devices known to this day, with which casting distributors may be provided do not allow long casting sequences to be carried out because of the necessity to replace one of the sensitive refractories after a relatively short time.
French patent no. 2065592 (SCHLOEMANN AKTIENGESELLSCHAFT) describes a device which allows interchangeable casting tubes to be positioned in the extension of a casting orifice of a metallurgical container.
The casting tubes designed to conduct the molten metal into.degree. a mculd or an ingot mould are wearing parts which are under substantial stress, to such an extent that their service life limits the casting time.
Owing to the erosion in the vicinity of the casting, as well as in the interior of the casting tubes, it proves necessary to replace one of the sensitive refractories after a relatively short time. These exchanges of casting tubes have so far prevented long casting sequences from being carried out.
In order to allow a tube to be changed in a continuous casting installation, British Patent no. 1,563,955 (CONCAST AG) proposes a metallurgical container provided with a sealing device and a casting tube through which the molten metal flows towards an intermediate receiver or towards a mould having only one opening with a small cross-section for introducing the casting tube.
A conveyor comprises guide means allowing the tube to be moved along a substantially horizontal path and pivoted from a substantially horizontal position towards a vertical position in such a manner as to allow positioning in the casting line without having to raise the intermediate distributor.
The positioning of the casting tube is carried out by fitting the outlet of the tube into an insert which consists of an exterior rim of the interior nozzle. This operation demands the complete interruption of the casting jet. The connection thus obtained has the disadvantage of affecting the imperviousness of the casting spout and consequently the quality of the metal. In order to protect the molten metal from oxidation, it has proved essential to have a device which provides an inert atmosphere in the vicinity of the casting orifice, for example using argon.
A stopper of refractory material for metallurgical containers designed for continuous casting is known from French patent No. 1,478,778. It comprises a movable refractory plate which can slide, under the action of a screw jack, along an upper fixed plate to a position closing the casting orifice. Levers are provided on which springs act at one end to press the movable plate against the upper plate in an impervious contact. Such a device allows the movable refractory plate of a sliding closing device to be easily replaced but does not allow the casting tube to be replaced without raising the distributor.
Numerous other mechanical devices have been developed to replace casting tubes mounted on the outlet orifice of a casting chamber. Among others, the applicant himself, by French Patent Application no. 2,424,085, has protected a device designed for the replacement, under a distributor, of casting tubes of refractory material. The tubes are charged or loaded transversely in an upright position on intermediate devices consisting, for example, of support slides brought into a casting position by sliding along a substantially horizontal straight path perpendicular to the casting axis.
The casting tubes are applied tightly against the distributor by a lever arm hinged on a common slide. Each lever is provided at its free end with a roller guided by a rail which is pushed downwards by a spring resting against the casting chamber.
In these known devices the juxtaposition of two consecutive tubes is impossible. Due to the construction of the support slide, there inevitably exists a gap between the plates of the tubes and this does not allow the tube to be changed without interrupting casting, Similarly, in order to discharge or remove a tube from the intermediate device and load or insert another tube, the plunging end of which tube is introduced into the continuous casting mould, the distributor must be irremediably raised in order to carry out the transverse loading operation.